The White House on Thursday tore into Democratic Rep. John Lewis for boycotting the opening of a new civil rights museum in Mississippi because President Trump is going.

"We think it's unfortunate that these members of Congress wouldn't join the president in honoring the incredible sacrifice rights leaders made to right the injustices in our history," White House press secretary Sarah Sanders said in a statement.

Lewis and his colleague Bennie Thompson, D-Miss., said in a joint statement earlier Thursday that Trump's upcoming attendance at the Saturday event will be an "insult" to the civil rights movement. For that reason, they both said they would not be going to the opening.

"President Trump's attendance and his hurtful policies are an insult to the people portrayed in this civil rights museum," the lawmakers said, citing "disparaging" comments they claimed the president has made about women, immigrants, and other groups.

Lewis and Trump exchanged sharp barbs earlier this year after the Democratic congressman declined to attend the president's inauguration.

Sanders said Trump hoped other lawmakers would make their way down to the museum and recognize that the civil rights "movement was about removing barriers and unifying Americans of all backgrounds."